The normal probability plot is a graphical technique for normality testing: assessing whether or not a data set is approximately normally distributed.
The data are plotted against a theoretical normal distribution in such a way that the points should form an approximate straight line. Departures from this straight line indicate departures from normality.
The normal probability plot is a special case of the Q–Q probability plot, for the case of a normal distribution.
Read more about Normal Probability Plot: Definition, Other Distributions, Examples
Famous quotes containing the words normal, probability and/or plot:
“When a man says that he is Jesus or Napoleon, or that the Martians are after him, or claims something else that seems outrageous to common sense, he is labeled psychotic and locked up in a madhouse. Freedom of speech is only for normal people.”
—Thomas Szasz (b. 1920)
“Liberty is a blessing so inestimable, that, wherever there appears any probability of recovering it, a nation may willingly run many hazards, and ought not even to repine at the greatest effusion of blood or dissipation of treasure.”
—David Hume (1711–1776)
“After I discovered the real life of mothers bore little resemblance to the plot outlined in most of the books and articles I’d read, I started relying on the expert advice of other mothers—especially those with sons a few years older than mine. This great body of knowledge is essentially an oral history, because anyone engaged in motherhood on a daily basis has no time to write an advice book about it.”
—Mary Kay Blakely (20th century)